How National Highways Are Numbered in India: NH Guide

Highway explainer: India’s national highway (NH) numbers are not random. The Ministry of Road Transport and Highways (MoRTH) adopted a systematic numbering framework in 2010 to help identify a road’s broad direction and geographical position. This guide explains the rules, what they cannot tell you, and how to check the current designation before a journey.

Why India changed national highway numbers

Older NH numbers did not consistently communicate where a highway was located or the direction in which it ran. In a letter dated 28 April 2010, MoRTH circulated Gazette notification S.O. 542(E) of 5 March 2010 and explained that the rationalised numbering system would indicate both direction and geographical region. Subsequent notifications and amendments have updated the designated network. A familiar old number may therefore differ from the one shown in a modern government schedule.

Odd and even NH numbers: the basic rule

• Even numbers: Major highways oriented broadly north–south are assigned even numbers, increasing from eastern India towards western India.
• Odd numbers: Major highways oriented broadly east–west are assigned odd numbers, increasing from northern India towards southern India.
• One- and two-digit numbers: These are generally used for primary national highway routes.
• Three-digit numbers: These commonly identify secondary routes, connectors or branches related to a primary highway.
• Letter suffixes: Some subsidiary routes have an A, B or other letter appended to their number.

These rules describe a numbering convention, not a guarantee that every kilometre of an NH runs in a straight compass direction. Roads bend, overlap other routes and connect multiple towns.

How three-digit branch numbers work

A three-digit designation can signal a secondary highway associated with a larger route. For example, numbers ending in 44 can identify branches associated with the NH 44 corridor. However, do not infer an exact origin, destination or junction from the digits alone: the legally notified description is the definitive reference. A letter suffix may distinguish a further spur or section.

Why old and new highway numbers can both appear

Historical maps, older business addresses and road signs may use a former NH designation. MoRTH has also issued instructions concerning kilometre stones and displaying renumbered routes. For navigation, use a recent map alongside official notifications; when researching a road, search both the old and current designation and confirm that they describe the same section.

How to verify a national highway number

1. Identify the exact road section and the nearby junctions or towns.
2. Check the latest applicable MoRTH notification or National Highways Act schedule for its legal designation.
3. Cross-check with an up-to-date road map and signage, particularly where routes overlap.
4. For toll information, separately check the relevant toll plaza and vehicle category. An NH number alone does not determine the toll charge.

Explore Toll.co.in’s National Highways directory, Highway Map, Toll Plaza directory and FASTag resources when planning your trip. Directory information should be cross-checked against current official records before travel.

Does an NH number tell you whether toll applies?

No. A national highway number identifies a designated route, not a uniform toll rate. Charges depend on the particular fee plaza, road section, applicable rules and vehicle class. Some sections may have no toll plaza at all. Use a current official fee source rather than calculating a charge from the route number.

Frequently asked questions

Are all even-numbered highways perfectly north–south?

No. The designation reflects the route’s broad orientation, not every bend or local segment.

Why does my old map show a different NH number?

India rationalised its numbering framework beginning in 2010, and later notifications can alter highway designations. Check the specific route against current government records.

Does a three-digit number always mean a shorter road?

No. It generally indicates a secondary or branch designation, not a fixed length. Check the actual route description and distance separately.

Official sources

• MoRTH: Rationalisation of National Highway numbering, circular dated 28 April 2010
• MoRTH: Standard operating procedure for kilometre stones following NH renumbering

Editorial note: This is a reference explainer, not a report of a new highway announcement or a live road-status advisory.